Characterization of the cloned promoter of the human initiation factor 4AI gene

Protein synthesis initiation factor 4AI (eIF-4AI) is ubiquitously expressed in eucaryotic cells. We characterized the eIF-4AI gene promoter cloned from human fibroblasts. The minimal promoter, localized to a region in the 5'-noncoding region adjacent to the first exon, consisted of approximately 300 base pairs (bp), 80% of which were identical with those in the corresponding mouse promoter. The minimal promoter contained TATA and CAAT motifs and consensus sequences binding to SP1 (three sites) and AP2 (one site). Deletion analyses of the promoter revealed that a 24-bp region near 5'-end of the minimal promoter was essential for the efficient transcription, although the AP2 site in the region was dispensable. A fluorescence polarization assay suggested that the plus strand of the 24-bp region, despite the lack of known consensus sequences binding to transcription factors except for AP2, bound to unknown nuclear protein(s) in a sequence specific manner.

Impaired male sex development in an infant with molecularly defined partial 9p monosomy: implication for a testis forming gene(s) on 9p

This paper describes a genetically male infant with impaired male sex development and partial 9p monosomy. The external genitalia were ambiguous with microphallus (penile length at birth 10 mm, mean age matched normal length 29 mm (SD 5)), hypospadias, and hypoplastic scrotum. The tests were undescended and severely hypoplastic (testis size at 12 months of age, right 8 x 5 x 4 mm and left 4 x 3 x 2 mm; mean age matched normal size, length 18 mm (SD 2), width 11 mm (SD 1). Cytogenetic studies showed a 46,XY,del(9)(p23) karyotype in all the 30 peripheral lymphocytes and 20 skin fibroblasts examined. Microsatellite analysis for a total of 13 loci assigned to the 9p22-24 region showed that the deleted chromosome 9 was of paternal origin and was missing a region distal to D9S168. Southern blot analysis for D9S47 also confirmed the 9p deletion. The sequence of SRY was normal. The results provide further support for the previously proposed hypothesis that a gene(s) for testis formation is present on the distal part of 9p and indicate in molecular terms that the putative testis forming gene(s) resides in the region distal to D9S168.

The Y specific growth gene(s): how does it promote stature?

Although the presence of a Y specific growth gene(s) (Y growth gene(s) on Yq has widely been accepted, it remains unknown how this gene promotes stature. In this report, we discuss the growth pattern in normal boys and girls and in patients with growth disorders informative for the Y growth gene(s). The results suggest that the Y growth gene(s) augments statural growth by controlling the sex steroid independent childhood growth pattern.

Ultra-high-resolution scanning electron microscopy of the continuity of cytoplasmic and luminal membranes in frog oxyntic cells

BACKGROUND

Despite numerous previous studies, the presumed continuity of the luminal and tubulovesicular membranes in frog oxyntic (oxyntico-peptic) cells remains to be convincingly demonstrated. This study was undertaken to clarify this question by ultra-high-resolution scanning electron microscopy of specially prepared frog stomach specimens before and during histamine stimulation.

METHODS

Fasted Japanese meadow frogs stimulated with histamine were used. Oxyntic cell cytoplasmic matrix was removed by the aldehyde-osmium-DMSO-osmium maceration procedure and impregnated with osmium-hydrazine. Specimens were examined without metal coating.

RESULTS

In the resting oxyntic cell, the luminal membrane had closely packed surface folds forming a rather flat surface with a few short microvilli. In the cytoplasm, flattened 200-500 nm vesicles were interconnected by numerous slender 20-60 nm tubules forming the tubulovesicular network. Occasional slender tubular branches were found in continuity with the luminal membrane. After histamine stimulation, the number and length of microvilli and surface folds increased, whereas the tubulovesicular membrane system decreased. Sites of clear continuity between the luminal and tubulovesicular membranes were not abundant but were clearly demonstrated in histamine-stimulated oxyntic cells. The small size of the tubules connecting the tubulovesicular system to the plasma membrane renders this observation by transmission electron microscopy very difficult. In these specimens, the clear continuity of the tubulovesicular network to the luminal plasma membrane became more evident.

CONCLUSIONS

This study confirms previous findings of increased luminal membrane and depletion of the tubulovesicle system. The demonstration of continuity between these two compartments in our SEM preparations supports the hypothesis of direct transfer of tubulovesicular membrane to oxyntic cell luminal secretory membrane.

Gene expression of granulocyte colony stimulating factor (G-CSF) in non-small cell lung cancer

Autonomous or continuous granulocyte colony-stimulating factor. (G-CSF)-production in malignant neoplasms is considered to induce leukocytosis without apparent infection. We examined G-CSF gene expression in human non-small cell lung cancer (NSCLC) and discussed its clinicopathological significance. Northern blot analysis revealed G-CSF gene expression in 14 of 84 surgical specimens (16.7%, 10/30 squamous cell carcinoma, 3/50 adenocarcinoma, 1/4 large cell carcinoma). Eight patients (57.1%, 8/14) with NSCLC showing G-CSF gene-expression had peripheral blood leukocytosis (> 8,000/microliter). The prognosis was significantly worse in 10 stage I or II NSCLC showing G-CSF gene expression (p < 0.01, Cox-Mantel test). These findings suggest that G-CSF gene expression is common event in the early stage of primary NSCLC, while it cannot completely explain the leukocytosis induced by lung cancer.

[The study of urgent pulmonary resections for lung cancer accompany with pneumonia]

We studied 10 lung cancer patients with pneumonia insusceptible of conservative treatment. All patients underwent urgent pulmonary resection to control their pneumonia induced by the tumor and to cure the cancer. The causes of pneumonia were bronchial obstruction by the tumor itself or aspiration of the tumor necrosis. The patients comprised 9 men and 1 women. The age range was 37 to 72 years with a median age of 57 years. There were obstructive pneumonia in 3 patients and aspiration pneumonia in 7 cases. The average size of tumor was about 4.7 and 7.5 cm, respectively. The histological type of lung cancer was squamous cell carcinoma in 6 and adenocarcinoma in 4. There were 1 stage 1,1 stage IIIA and 3 stage IIIB tumors. Lobectomy was performed in 8 patients and pneumonectomy in 2 patients. Nine patients underwent the operation under one-lung ventilation. A median period of preoperative administration of antibiotics was 6.2 days. The curative operation for lung cancer was performed in 3 patients and non-curative operation in 7 patients. Postoperative complications were pneumonia in 2, subcutaneous abscess in 2 and arrhythmia in a case of pneumonectomy. All non-curative patients died in 5 years, but two curative patients survived long time for 31 and 75 months, respectively. We performed urgent pulmonary resection for lung cancer patients to cure fatal pneumonia and cancer. There were no hospital death. Urgent pulmonary resection could prevent early death caused by fatal pneumonia by tumor itself.

Duodenal and gastric cell regenerating epithelia on margins of human duodenal ulcer and presence of H. pylori--an electron microscopic study

Specimens from 22 cases of human duodenal ulcers obtained at surgery were studied by transmission and scanning electron microscopy. Observations were focused on the ulcer margins which always showed some evidence of healing by simple cuboidal epithelial cells migrating on the ulcer base. Two types of regenerating epithelia (RE) were found: the intestinal and the gastric cell types. The intestinal type RE originating from intestinal epithelium of the surrounding epithelium of the ulcer edge was composed of immature enterocytes, which differentiated into absorptive and goblet cells, and formed presumptive crypts and villi. The gastric type RE grew from adjacent metaplastic gastric mucosa at the edge of the ulcer and consisted of immature cells, which developed into mucous cells. Some ulcers had RE of both intestinal cell and gastric cell origin. In most margins, the RE was of only one cell type, but in others both intestinal and gastric type cells were present. In more developed regions both types formed presumptive glands. The basal lamina was frequently missing near the leading edge. This corresponded to degeneration and necrosis of RE, especially in areas of severe inflammatory foci. Helicobacter (H.) pylori colonization on gastric metaplastic epithelium was observed in about one third of the ulcer cases. In the surrounding epithelium of ulcers colonized with H. pylori there were degenerative changes, disruption of cell membranes, and massive cell exfoliation resulting in denuded lamina propria. Some gastric type RE was also colonized with H. pylori. No infection was found on intestinal epithelia. These findings suggest that H. pylori may be important in the development of duodenal ulcers as well as in the prevention or delay of ulcer healing.

Saxitoxin as a toxic principle of a freshwater puffer, Tetraodon fangi, in Thailand

Saxitoxin was identified in a freshwater puffer, Tetraodon fangi, which caused food poisoning in Thailand. Tetrodotoxin, a puffer toxin, was not detected in the species by the HPLC-fluorometric analysis, showing that tetrodotoxin is absent or under any detectable level. The result of this study shows that saxitoxin can be a major toxin in puffer.

Fluid flow induces enhancement of the Egr-1 mRNA level in osteoblast-like cells: involvement of tyrosine kinase and serum

It is widely accepted that mechanical loading is necessary to construct the architecture of bone and to maintain bone mass. However, the mechanism of how bone cells respond to mechanical stimuli is not known. To clarify this, we stimulated osteoblast-like MC3T3E1 cells by mechanical shaking of the culture dishes and found that the level of the egr-1 gene, which is an early response gene induced by growth factors or serum and encodes a transcription factor, increased 15-45 min after the shaking, with a peak at 30 min. The egr-1 gene product increased 1 h after the shaking. The egr-1 gene elevation was not blocked by prior exposure to indomethacin, saralasin, Rp-cAMP, A23187, and colchicine, and it was blocked partially by cytochalasin D, H-7, and prolonged exposure to TPA. On the other hand, a prior incubation with cycloheximide, DRB, genistein, herbimycin A, and BAPTA/AM completely blocked the egr-1 gene level enhanced by shaking the culture dishes. Moreover, we found that in serum-deprived cells the egr-1 gene response to shaking was not induced. These results suggested that the egr-1 gene response is regulated at the transcriptional level and that it involves tyrosine kinase as well as labile or de novo protein and requires a particular level of intracellular calcium and serum.

Testicular histopathology in congenital lipoid adrenal hyperplasia: a light and electron microscopic study

This paper describes the testicular histopathology in 2 male patients with congenital lipoid adrenal hyperplasia who underwent orchiectomy at age 7 (case 1) and 12 (case 2) years, respectively. In both cases, seminiferous tubules were normal in diameter (mean: case 1 88.7 microm; case 2 115.9 microm) and consisted of an age-appropriate number of type A spermatogonia (mean: case 1 1.7/tubule; case 2 4.0/tubule) and an increased number of Sertoli cells (mean: case 1 34.7/tubule; case 2 27.9/tubule). The interstitial space was abundant and contained normal to increased numbers of Leydig cells (mean: case 1 4.0/ tubule; case 2 6.1/tubule) that were filled with lipid droplets. We suspect that lipid accumulation in Leydig cells is consistent with defective conversion of cholesterol into pregnenolone and thus constitutes the characteristic feature of this disease, while the remaining findings appear to be common to disorders associated with hypergonadotropic hypogonadism.

A CT using longitudinally detected ESR (LODESR-CT) of intraperitoneally injected nitroxide radical in a rat's head

We have developed an in vivo longitudinally detected ESR (LODESR) imaging system operating at 700 MHz based on a loop-gap resonator and a pair of saddle-type pickup coils. A good linear relationship between the LODESR signal intensity and the applied power in a range up to 15.8 W was obtained. The detection of LODESR signals was barely affected by variations in the resonant properties. The characteristic of LODESR is suitable for in vivo examination. Using this system, we succeeded in obtaining LODESR-CT images of the head region of a rat after the intraperitoneal injection of a nitroxide radical.

A case of skeletal dysplasia with advanced carpal ossification and "monkey wrench" appearance of the femora: mild Desbuquois dysplasia?

We report on a 14-year-old Japanese boy with radiographic features resembling those of Desbuquois dysplasia, including advanced carpal ossification, a "monkey wrench" appearance of the proximal femora, mild spondylar dysplasia, and generalized osteopenia. In contrast to the hitherto known patients with this disorder, however, his birth length was normal, and his short stature, which became apparent postnatally, was much milder than that of the previously reported cases (approximately -5 SD of average), and the joint laxity was more subtle. In addition, facial dysmorphism was absent, as were radial deviation of the second fingers and thoracolumbar kyphoscoliosis.

CONCLUSION

The present patient may represent the mildest end of the variable phenotypic manifestation of the recently described Desbuquois dysplasia.

P-glycoprotein-mediated acquired multidrug resistance of human lung cancer cells in vivo

We examined whether the increased expression of P-glycoprotein (P-gp) encoded by the human multidrug resistance gene MDR1 is related to the acquired multidrug resistance of lung cancer in vivo. We estimated the chemosensitivity of lung cancer xenografts (LC-6, adenocarcinoma; Lu-24, small-cell cancer) by calculation of relative tumour growth (T/C%, treated/control) in vivo, based on statistical significance determined by the Mann-Whitney U test (P < 0.01, one-sided). MDR1 gene expression levels were evaluated by reverse transcription-polymerase chain reaction (RT-PCR) assay. P-gp production and P-gp localisation were examined by Western blotting and by immunohistochemical analysis respectively. LC-6 and Lu-24 were initially sensitive to both vincristine (VCR, 1.6 mg kg-1: LC-6, 45%; Lu-24, 39%) and doxorubicin (DOX, 12 mg kg-1: LC-6, 26%; Lu-24, 27%) in vivo. VCR-resistant variants (LC-6R, 66% and Lu-24R, 68%) selected with VCR (0.4 mg kg-1, x 9) significantly acquired cross-resistance to DOX (LC-6R, 55% and Lu-24R, 55% respectively). RT-PCR assay showed increased levels of MDR1 expression in LC-6R and Lu-24R with stable MDR1 expression levels. P-gp expression levels were elevated, and the percentage of P-gp-positive tumour cells increased in both LC-6R and Lu-24R. These results suggest that P-gp/MDR1 overexpression is related to acquired multidrug resistance in lung cancer in vivo.

[Clinicopathological study of pulmonary hamartoma with special reference to 6 patients who also had another tumor]

We studied 22 patients in whom intrapulmonary hamartoma was diagnosed between 1975 and 1994. Twelve were men and 10 were women, and their ages ranged from 20 to 72 years (averaged: 52.5). The sizes of the hamartomas ranged from 5 mm to 3 cm. Five patients also had other types of cancer (ling 3, colon 1, thyroid 1) and one had a mediastinal tumor (1). In those 6 patients, the hamartomas had to be distinguished from intrapulmonary metastasis. In 2 of those 6, thoracoscopic surgery was useful for obtaining sufficient materials for diagnosis. In one patient immunohistochemical analysis with anti-PCNA (proliferative cell nuclear antigen) antibody was useful in distinguishing leiomyomatous hamartoma from benign metastatic leiomyoma.

A 3D- and 4D-ESR imaging system for small animals

A new version of in vivo ESR-CT system composed of custom-made 0.7 GHz ESR spectrometer, air-core magnet with a field-scanning coil, three field-gradient coils, and two computers enables up- and down-field, and rapid magnetic-field scanning linearly controlled by computer. 3D-pictures of distribution of nitroxide radicals injected in brains and livers of rats and mice were obtained in 1.5 min with resolution of 1 mm. We have also succeeded in obtaining spatial-time imagings of the animals.

The effect of TNP-470 on cell proliferation and urokinase-type plasminogen activator and its inhibitor in human lung cancer cell lines

The plasminogen activator system has been found to modulate neoplastic spread and angiogenesis in tumors. An angiogenesis inhibitor, TNP-470, has been shown to possess potent antitumor activities in various types of cancer cells. We therefore investigated the inhibitory effect of TNP-470 on cancer cell proliferation, and the suppressive effect of TNP-470 on urokinase-type plasminogen activator (u-PA) and its inhibitor (PAI-1), in human lung cancer cell lines in vitro. TNP-470 inhibited cell proliferation in a dose-dependent manner in both cell lines. u-PA and PAI-1 in culture supernatants were suppressed with the concentrations of TNP-470, in association with a decrease in viable cancer cells. Unchanged serum levels of u-PA and PAI-1 would be of great advantage to the diseased patients, since the plasminogen activator system has a crucial function in the process of distant metastasis.

Programmed cell death in rat microglia is controlled by extracellular adenosine

The induction of programmed cell death by adenosine was investigated in cultured rat microglial cells using the enzyme-linked immunosorbent assay (ELISA) for determining DNA fragmentation. Twelve hours exposure to micromolar levels of the unselective adenosine receptor agonist 2-chloro-adenosine led to the appearance of DNA fragments in the cytosolic fraction preceding damage of the plasma membrane. This effect was still seen in the presence of an adenosine uptake blocker. Conventional A1, A2 or A3 agonists and antagonists were rather ineffective, suggesting mediation via an atypical adenosine receptor subtype. Microglial DNA fragmentation was inhibited by H-7 and staurosporine but not by dibutyryl-cyclic AMP, pointing to a protein kinase C linked mechanism. Such an induction of programmed cell death by an elevation of the extracellular adenosine concentration may provide an endogenous control mechanism to limit the function of activated microglial cells.

Follicular dendritic cells adhere to fibronectin and laminin fibers via their respective receptors

The expression of adhesion molecules on human tonsillar follicular dendritic cells (FDCs) in the secondary lymphoid follicle (LF) in vivo and in vitro was investigated using cryostat sections and cytospin preparations of FDCs isolated with a magnetic cell sorter, respectively. FDCs were immunochemically positive for Mac-1 (CD11b), sialyl-Lex (CD15s), CD22, integrin beta 1 (CD29), CD40, very late activation antigen (VLA)-alpha 3 (CD49c), VLA-alpha 5 (CD49e), VLA-alpha 6 (CD49f), intercellular adhesion molecule (ICAM)-3 (CD50), ICAM-1 (CD54), B7 (CD80), and vascular cell adhesion molecule (VCAM)-1 (CD106). With respect to ligands on B cells for these adhesion molecules, the CD11b-CD54, CD50-leukocyte function-associated molecule (LFA)-1 (CD11a/18), and CD106-VLA-4 (CD49d/29) interactions in the apical light (ALZ) and basal light (BLZ) zones; the CD15s-L-selectin (CD62L) and CD106-CD49d/29 interactions in the mantle zone; and the CD54-CD11a/18 interaction in the entire LF may participate in FDC-B cell adhesion. Namely, the adhesion molecules participating in FDC-B cell interactions may differ in each of the five zones. Furthermore, the immunochemical evidence that FDCs were fibronectin (VLA-5, CD49e/29) and laminin (VLA-6, CD49l/29) receptor-positive discussed above was confirmed by immunoelectron microscopy and binding assays. Immunoelectron microscopy revealed fibers surrounded by cytoplasmic FDC extensions that were CD29-, CD49e-, and CD49f-positive. In the binding assays, the numbers of FDCs bound to fibronectin- and laminin-coated dishes and LFs of cryostat sections of human tonsils were reduced markedly by pretreatment with monoclonal antibodies against CD29, CD49e, and CD49f. These data indicate clearly that FDCs bind to reticulin and laminin fibers in LFs via their respective receptors.

Occurrence of tetrodotoxin in Alexandrium tamarense, a causative dinoflagellate of paralytic shellfish poisoning

A significant amount of tetrodotoxin was identified in the cultured cells of Alexandrium tamarense, a causative dinoflagellate of paralytic shellfish poisoning. This result supports the hypothesis that both tetrodotoxin and paralytic shellfish toxins can be detected in organisms which possess either of them, although their proportion is different individually. The present result also supports our previous finding that A. tamarense is the origin of tetrodotoxin detected in the highly toxic scallop Patinopecten yessoensis during the bloom of A. tamarense.

Dynamic electron spin resonance (ESR) imaging of the distribution of spin labeled dextran in a mouse

The nitroxide group 2,2,6,6-tetramethylpiperidine-1-oxyl (TEMPO) was covalently bound to a dextran via an N-acetamido linkage to produce a novel spin probe, TEMPO-dextran (TEMPO-DX), which circulates for long time periods in an animal without metabolic degradation. TEMPO-DX was stable in mice, while small TEMPO analogs quickly disappeared after administration. Since dextran was reduced somewhat in size during synthesis, the resultant spin-labeled dextran could be excreted through the kidney. A strong L-band electron spin resonance signal was obtained shortly after intravenous administration of TEMPO-DX into the tail vein of a mouse, from which three-dimensional images of specific organs were calculated. The signal was found to persist for well over 1 h.

Contrast-enhanced radiographic computed tomographic findings in patients with straight back syndrome

Straight back syndrome (SBS) is usually diagnosed by physical and chest radiographic findings. Radiographic computed tomographic (CT) findings are very useful for the diagnosis and the evaluation of its severity. The purpose is to evaluate the relationship between chest X-ray film and CT findings.

SUBJECTS

We evaluated 26 patients (SBS group) and 11 normal subjects (control group). SBS group consisted of 15 patients without structural heart disease (group I) and 11 patients with other heart disease (group II).

METHODS

(1) On the chest X-ray film, antero-posterior diameter (APD) of the thorax, transthoracic diameter (TTD), and APD/TTD ratio were measured. (2) On the CT image, three parameters were calculated; APD of the left atrium (LA diameter), APD/transverse diameter ratio of the heart (flattening ratio) and left side shift ratio of the heart (shifting ratio). (3) CT parameters were compared with APD/TTD ratio in patients and control group.

RESULTS

(1) APD/TTD ratio was smaller in group I and II than control group (30.0 +/- 5.4, 30.5 +/- 4.0 v 44.6 +/- 2.7%, p < .001). (2) LA diameter was smaller in group I and II than control group (23.2 +/- 4.1, 26.0 +/- 8.6 v 30.0 +/- 6.5 mm, p < .01). Flattening ratio was also smaller in group I and II than control group (59.2 +/- 9.4, 61.8 +/- 8.6 v 75.4 +/- 13.2%, p < .01). Shifting ratio was greater in group I and II than control group (10.9 +/- 5.0, 11.9 +/- 4.5 v 8.4 +/- 4.0%, p < .01). (3) APD/TTD ratio correlated with LA diameter (r = .39, p < .05) and flattening ratio (r = .53, p < .001). APD/TTD ratio did not correlate with shifting ratio (r = -.27, NS).

CONCLUSIONS

APD/TTD ratio correlated with LA diameter and flattening ratio rather than shifting ratio. LA diameter and flattening ratio on the CT image were more useful for evaluating the severity.